Fetal growth potential reflects a complex regulatory system delivered by genetic and environmental factors acting directly on the fetus or through the placenta. Compromise of this potential, as seen in intrauterine growth restriction (IUGR), is associated with increased perinatal mortality and short and long term morbidity. The expression of several genes has been shown to be disturbed in placentas of fetuses with growth restriction. However, the primary causes for these changes have not yet been elucidated. I proposed that epigenetic mechanisms, specifically DNA methylation, may be involved in placental development leading to modulation of the expression of specific genes, and that their altered regulation will impact fetal development and growth. My primary objective was to identify DNA methylation variation in placenta, in association with variation of gene expression and with poor fetal growth. I used a global genomic screening approach, with 24 selected placental samples, from newborns considered IUGR or normal controls, to identify candidate target genomic regions carrying epigenetic alterations. Candidate regions were followed up, by expression analysis of corresponding regulated genes, for associations with altered expression and by targeted methylation analysis in an expanded cohort of 170 samples, for associations with birthweight percentile. I analyzed methylation variation at imprinting centers (IC), gene promoters and CpG islands. In two genome-wide case control screening studies using distinct commercial microarray platforms I identified approximately 68 differentially methylated autosomal candidate genomic regions overlapping gene promoters. Hypomethylated CpGs mapping to gene promoters were found to be more abundant in placentas of growth restricted newborns than in controls. One of the most interesting candidates, WNT2, was analyzed in an extended sample cohort and showed an association of high promoter methylation to low expression as well as low birthweight percentile. This gene is involved in a pathway that diverts cells from programmed apoptosis. It is highly expressed in placenta, and in mice, targeted biallelic inactivation of Wnt2 has been shown to cause poor growth and perinatal death in 50% of the affected pups. These findings support the hypothesis that dysregulation of epigenetic mechanisms are involved in abnormal placental development and can impact fetal growth.

This dissertation discusses research on Canada’s collaboration with emerging economies, specifically Brazil and India, in the field of health biotechnology. In recent years Canada has shown interest in engaging with emerging economies including Brazil and India in S&T fields. However, little is known about the levels and characteristics of such collaboration. Without greater understanding of this phenomenon it is difficult to inform public policy on how to best encourage collaboration. In this dissertation, the levels of Canada-emerging economies research and entrepreneurial collaboration are gauged. The motivations driving Canada-emerging economies research as well as entrepreneurial collaboration, its challenges and outcomes are examined. The roles of wider institutional actors – funding agencies, intellectual property experts, regulators, etc – in both Canada and the two emerging economies that support international collaboration are analyzed. The research reveals that north-south collaboration in health biotechnology has the potential to lead to a wide range of scientific and commercial benefits for both partners. They include access to expertise, technologies, biodiversity, as well as increasing potential to publish in high impact journals. The benefits are mutual. Northern academics and entrepreneurs are not necessarily in a dominant position in the partnerships, thus contradicting stereotypical notions of partners in north-south relationships. The systems of innovation conceptual framework is useful to uncover how institutions in both the north and the south shape S&T collaboration, and also to develop multi-pronged policy approaches to promote such partnerships and mitigate risks. The framework enables moving away from a donor-recipient, linear model of S&T interactions between the north and the south, and towards conceptualizing north-south collaboration as complex interplay of two innovation systems.

Fetal growth potential reflects a complex regulatory system delivered by genetic and environmental factors acting directly on the fetus or through the placenta. Compromise of this potential, as seen in intrauterine growth restriction (IUGR), is associated with increased perinatal mortality and short and long term morbidity. The expression of several genes has been shown to be disturbed in placentas of fetuses with growth restriction. However, the primary causes for these changes have not yet been elucidated. I proposed that epigenetic mechanisms, specifically DNA methylation, may be involved in placental development leading to modulation of the expression of specific genes, and that their altered regulation will impact fetal development and growth. My primary objective was to identify DNA methylation variation in placenta, in association with variation of gene expression and with poor fetal growth. I used a global genomic screening approach, with 24 selected placental samples, from newborns considered IUGR or normal controls, to identify candidate target genomic regions carrying epigenetic alterations. Candidate regions were followed up, by expression analysis of corresponding regulated genes, for associations with altered expression and by targeted methylation analysis in an expanded cohort of 170 samples, for associations with birthweight percentile. I analyzed methylation variation at imprinting centers (IC), gene promoters and CpG islands. In two genome-wide case control screening studies using distinct commercial microarray platforms I identified approximately 68 differentially methylated autosomal candidate genomic regions overlapping gene promoters. Hypomethylated CpGs mapping to gene promoters were found to be more abundant in placentas of growth restricted newborns than in controls. One of the most interesting candidates, WNT2, was analyzed in an extended sample cohort and showed an association of high promoter methylation to low expression as well as low birthweight percentile. This gene is involved in a pathway that diverts cells from programmed apoptosis. It is highly expressed in placenta, and in mice, targeted biallelic inactivation of Wnt2 has been shown to cause poor growth and perinatal death in 50% of the affected pups. These findings support the hypothesis that dysregulation of epigenetic mechanisms are involved in abnormal placental development and can impact fetal growth.

This dissertation discusses research on Canada’s collaboration with emerging economies, specifically Brazil and India, in the field of health biotechnology. In recent years Canada has shown interest in engaging with emerging economies including Brazil and India in S&T fields. However, little is known about the levels and characteristics of such collaboration. Without greater understanding of this phenomenon it is difficult to inform public policy on how to best encourage collaboration. In this dissertation, the levels of Canada-emerging economies research and entrepreneurial collaboration are gauged. The motivations driving Canada-emerging economies research as well as entrepreneurial collaboration, its challenges and outcomes are examined. The roles of wider institutional actors – funding agencies, intellectual property experts, regulators, etc – in both Canada and the two emerging economies that support international collaboration are analyzed. The research reveals that north-south collaboration in health biotechnology has the potential to lead to a wide range of scientific and commercial benefits for both partners. They include access to expertise, technologies, biodiversity, as well as increasing potential to publish in high impact journals. The benefits are mutual. Northern academics and entrepreneurs are not necessarily in a dominant position in the partnerships, thus contradicting stereotypical notions of partners in north-south relationships. The systems of innovation conceptual framework is useful to uncover how institutions in both the north and the south shape S&T collaboration, and also to develop multi-pronged policy approaches to promote such partnerships and mitigate risks. The framework enables moving away from a donor-recipient, linear model of S&T interactions between the north and the south, and towards conceptualizing north-south collaboration as complex interplay of two innovation systems.

The Fibronectin leucine-rich transmembrane (Flrt) gene family has been implicated in FGF signaling, which is crucial for coordinating craniofacial morphogenesis and epithelial mesenchymal interactions (EMI). The gene expression patterns of Flrt1, Flrt2 and Flrt3 were analyzed during critical stages of murine midfacial development from 9.5-15.5 dpc. Flrt2 and Flrt3 were observed to have unique expression patterns in the midface, whereas Flrt1 did not. From 10.5-12.5dpc, Flrt2 was expressed in the mesenchyme of the medial nasal process(MNP). Flrt3 was expressed in the mesenchyme of the lateral nasal process (LNP) and MNP. From 13.5-15.5dpc, Flrt2 was expressed in the oral ectomesenchyme of the palatal shelves, whereas Flrt3 was expressed in the medial edge and oral epithelium. Both Flrt2 and Flrt3 were expressed in different sites of the developing tooth buds and hair follicles. This suggests that Flrt2 and Flrt3 have unique roles during craniofacial morphogenesis, whereas Flrt1 may have a more generalized role.

Objective: This thesis aims to construct a framework for studying vitamin D deficiency in young Canadian children. Methods: A practice based research network was created to collect vitamin D data from children 1-5 years of age in Toronto, Canada (TARGet Kids!). A cross-sectional pilot study was completed and a larger study proposed to determine the prevalence and predictors of low vitamin D. Results: The prevalence of low vitamin D (<50nmol/L) in the pilot study was 32% (29/92, 95% CI: 22-42%). Using multivariable linear regression, lower vitamin D level was associated with lower milk volume, higher BMI and watching TV during snacks. A larger study involving 2400 children 1-5 years of age has been proposed. Interpretation: Pilot data has suggested that 30-80% of toddlers in this setting have low vitamin D. A study to clarify these findings and form the basis of a large longitudinal vitamin D cohort has been proposed.

Objective: This thesis aims to construct a framework for studying vitamin D deficiency in young Canadian children. Methods: A practice based research network was created to collect vitamin D data from children 1-5 years of age in Toronto, Canada (TARGet Kids!). A cross-sectional pilot study was completed and a larger study proposed to determine the prevalence and predictors of low vitamin D. Results: The prevalence of low vitamin D (<50nmol/L) in the pilot study was 32% (29/92, 95% CI: 22-42%). Using multivariable linear regression, lower vitamin D level was associated with lower milk volume, higher BMI and watching TV during snacks. A larger study involving 2400 children 1-5 years of age has been proposed. Interpretation: Pilot data has suggested that 30-80% of toddlers in this setting have low vitamin D. A study to clarify these findings and form the basis of a large longitudinal vitamin D cohort has been proposed.

The Fibronectin leucine-rich transmembrane (Flrt) gene family has been implicated in FGF signaling, which is crucial for coordinating craniofacial morphogenesis and epithelial mesenchymal interactions (EMI). The gene expression patterns of Flrt1, Flrt2 and Flrt3 were analyzed during critical stages of murine midfacial development from 9.5-15.5 dpc. Flrt2 and Flrt3 were observed to have unique expression patterns in the midface, whereas Flrt1 did not. From 10.5-12.5dpc, Flrt2 was expressed in the mesenchyme of the medial nasal process(MNP). Flrt3 was expressed in the mesenchyme of the lateral nasal process (LNP) and MNP. From 13.5-15.5dpc, Flrt2 was expressed in the oral ectomesenchyme of the palatal shelves, whereas Flrt3 was expressed in the medial edge and oral epithelium. Both Flrt2 and Flrt3 were expressed in different sites of the developing tooth buds and hair follicles. This suggests that Flrt2 and Flrt3 have unique roles during craniofacial morphogenesis, whereas Flrt1 may have a more generalized role.

The current thesis directly investigated whether changes in the neural correlates of self-regulation (SR) are associated with the effectiveness of treatment for children’s externalizing problems. In order to test this, seventy-one children 8–12 years of age with clinical levels of externalizing behaviour and their parents completed a 12-week cognitive behavioural therapy program (12 sessions) with a parent management training component that was aimed at improving SR. Electroencephalogram (EEG) correlates of SR were evaluated before and after treatment with a go/no-go task requiring inhibitory control on the children. Results showed that event-related potential (ERP) correlates of SR, such as the frontal N2 and frontal P3 event-related potential magnitudes, differed between the clinical sample and a matched comparison group before treatment: the clinical sample had larger N2 magnitudes and smaller frontal P3 magnitudes. Children who showed improvement (45%) with treatment demonstrated a decrease in the magnitude of the N2 in comparison with children who did not improve. For improvers only, source analysis during the time period of the N2 modeled activation decreases in dorsomedial and ventromedial prefrontal cortex as well as the anterior medial temporal lobe. A decrease in N2 magnitudes and corresponding reductions in source activation, in children who improved with treatment, might reflect improved efficiency in the neural mechanisms of SR. These findings may be important steps toward a better identification of neural markers of SR and a better understanding of the mechanisms of treatment efficacy.

The current thesis directly investigated whether changes in the neural correlates of self-regulation (SR) are associated with the effectiveness of treatment for children’s externalizing problems. In order to test this, seventy-one children 8–12 years of age with clinical levels of externalizing behaviour and their parents completed a 12-week cognitive behavioural therapy program (12 sessions) with a parent management training component that was aimed at improving SR. Electroencephalogram (EEG) correlates of SR were evaluated before and after treatment with a go/no-go task requiring inhibitory control on the children. Results showed that event-related potential (ERP) correlates of SR, such as the frontal N2 and frontal P3 event-related potential magnitudes, differed between the clinical sample and a matched comparison group before treatment: the clinical sample had larger N2 magnitudes and smaller frontal P3 magnitudes. Children who showed improvement (45%) with treatment demonstrated a decrease in the magnitude of the N2 in comparison with children who did not improve. For improvers only, source analysis during the time period of the N2 modeled activation decreases in dorsomedial and ventromedial prefrontal cortex as well as the anterior medial temporal lobe. A decrease in N2 magnitudes and corresponding reductions in source activation, in children who improved with treatment, might reflect improved efficiency in the neural mechanisms of SR. These findings may be important steps toward a better identification of neural markers of SR and a better understanding of the mechanisms of treatment efficacy.